Oxygen gas can be prepared by heating potassium chlorate according to the following equation:

2KClO3(s) → 2KCl(s) + 3O2(g)

The product gas, O2, is collected over water at a temperature of 20 °C and a pressure of 747 mm Hg. If the wet O2 gas formed occupies a volume of 6.42 L, the number of grams of O2 formed is g. The vapor pressure of water is 17.5 mm Hg at 20 °C.

The number of grams of formed is 8.32 g

Explanation:

According to the ideal gas equation:

P = Pressure of the gas = Total pressure - presure of water = (747-17.5)mm Hg= 729.5 mm Hg = 0.96 atm     (760mmHg=1atm)

V= Volume of the gas = 6.42 L

n=  moles of gas = ?

T= Temperature of the gas in kelvin =

R= Gas constant = 0.0821Latm/Kmol

The balanced chemical reaction is:

Mass of produced=

Thus number of grams of formed is 8.32 g

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

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